22 lines
719 B
TypeScript
22 lines
719 B
TypeScript
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import { useEffect, useState } from 'react'
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/**
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* Returns the last value of type T that passes a filter function
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* @param value changing value
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* @param filterFn function that determines whether a given value should be considered for the last value
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*/
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export default function useLast<T>(
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value: T | undefined | null,
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filterFn?: (value: T | null | undefined) => boolean
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): T | null | undefined {
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const [last, setLast] = useState<T | null | undefined>(filterFn && filterFn(value) ? value : undefined)
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useEffect(() => {
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setLast((last) => {
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const shouldUse: boolean = filterFn ? filterFn(value) : true
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if (shouldUse) return value
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return last
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})
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}, [filterFn, value])
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return last
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}
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